The encoding/xml package in Go versions 1.15 and earlier does not correctly preserve the semantics of directives during tokenization round-trips, which allows an attacker to craft inputs that behave in conflicting ways during different stages of processing in affected downstream applications.

An input validation vulnerability was found in Go. From a generated go file (from the cgo tool), it is possible to modify symbols within that object file and specify code. This flaw allows an attacker to create a repository that includes malicious pre-built object files that could execute arbitrary code when downloaded and run via go get or go build while building a Go project. The highest threat from this vulnerability is to confidentiality, integrity, as well as system availability.